Dynamic Properties of Plain Concrete in Triaxial Stress State

Abstract

There was experimental investigation of plain concrete dynamic behavior at high strain rates using a custom-designed, triaxial, servo-hydraulic controlled testing machine with over 60 cubic specimens in this study. A gradually increasing force was used for axial loading of each specimen at a constant strain rate at 10 supra -5 second supra -1, 10 supra -4 second supra -1, or 10 supra -3 second supra -1 and laterally confined at a 0, 4, 8, 12, or 16 MPa (0, 0.58, 1.16, 1.74, or 2.32 ksi) constant pressure. At each strain rate, there was analysis and discussion of axial stress-strain curves under confining pressures. Test results indicated that there were significant increases according to confining pressure of both ultimate strength and its corresponding strain. There was development of empirical equations accounting for triaxial stress and strain rate effects. There is substantial ultimate strength increases under low confinement and moderate increases under high confinement with increasing strain rate.